Renal trauma


(1) Human urinary system: (2) kidney; (3) renal pelvis; (4) ureter; (5) urinary bladder (6) urethra.
Additional structures: (7) adrenal gland; (8) renal artery and vein; (9) inferior vena cava; (10) abdominal aorta; (11) common iliac artery and vein; (12) liver; (13) large intestine; (14) pelvis.
Renal anatomy.
Perinephric space with exaggerated pararenal space to show retroperitoneal structures. Perinephric bridging septa are seen between the left kidney and the adjacent renal fascia.
  • Approximately 10% of blunt injuries include renal trauma
  • Blunt mechanism 9x more common than penetrating[1]

Clinical Features

  • Flank pain
  • Hematuria (gross or microscopic)
  • Page kidney (late finding) - hypertension resulting from long-standing compression of from renal parenchyma by subcapsular hematoma

Differential Diagnosis

Abdominal Trauma


Delayed-phase CT shows fluid filling the right perinephric space in a patient following blunt trauma. The kidney has been lacerated (short arrow), and urinary contrast extravasation is shown posteriorly (long arrow)


  • CT with contrast


AAST Grading System for renal injuries

  • Non-operative management[2]
    • Grade I: Cortex contusion
    • Grade II: Cortex laceration
  • Possible operative management
    • Grade III: Corticomedullary junction laceration
    • Grade IV: Collecting system laceration
  • Operative management
    • Grade V: Shattered kidney, thrombosis of renal artery, avulsion of hilum


  • Based on grade of injury (above)
  • Prophylactic IV antibiotics for grade IV, V injuries (first generation cephalosporin, ciprofloxacin, or ampicillin and gentamicin)
  • Absolute indications for operative renal exploration and intervention:
    • Life-threatening hemorrhage
    • Expanding, pulsatile, or non-contained retroperitoneal hematoma
    • Renal avulsion injury
  • Page kidney treatment involves ACE inhibitor and possible drainage of hematoma



  • Penetrating renal injuries
  • Gross hematuria
  • Grade II or higher injury


  • Microscopic hematuria and no indication for imaging
  • Isolated renal trauma with Grade I injury
    • Ensure close followup and instruct no heavy lifting

See Also


  1. Miller, K. S. and McAninch, J. W. (1995) ‘Radiographic Assessment of Renal Trauma’, The Journal of Urology, pp. 352–355.
  2. Shariat, S. F., Roehrborn, C. G., Karakiewicz, P. I., Dhami, G. and Stage, K. H. (2007) ‘Evidence-Based Validation of the Predictive Value of the American Association for the Surgery of Trauma Kidney Injury Scale’, The Journal of Trauma: Injury, Infection, and Critical Care, 62(4), pp. 933–939.